ヒト型糖鎖が結合した組織性プラスミノーゲンアクチベーターの生産とその炭水化物部分の役割

概要

論文の詳細を見る
To begin the examination of the role of human type carbohydrate moiety of tissue plasminogen activator(t-PA) on the binding of the enzyme to fibrin，the naturally glycosylated enzyme was produced by microcarrierculture of human cells established from normal uterine muscle. The cells grown on microcarrers in Haunks' MEM supplemented with 10 % FBS (1.6 x 10 6 cells/ml) rapidly detached themselves from microcarrier in aserum-free medium (t-PA production medium) within 5 days, and it was difficult to produce t-PA for long time (t-PA production: an average of 3 IU/ml/day over 5 days). Addition of 0.5% beef extract to the serum-freemedium suppressed their detaching from microcarriers. By regulating the pH (7.4) and dissolved oxygen(4 ppm) of the serum free medium，the cell density of microcarrier culture increased to 1.2 x10 7 cells/ml and t-PAwas produced over 38 days (t-PA production: an average of 836 IU/ml/day over 38 days). Native t-PAs purifiedto homogeneity from the culture broth had the molecular weight of 63,000 and 65,000 containing 5.6 and 8.5 %carbohydrate，respectively (molecular mass of protein moiety was calculated to be 59,500). By enzymaticdigestion of carbohydrate moiety in native t-PA，we obtained partially deglycosylated t-PA with molecularweights of 60,000 and 62,000. Completely deglycosylated t-PA was obtained by t-PA production in thepresence of 10μg/ml tunicamycin (N-glycosylation inhibitor). This suggests that N-glycosylationof t-PAoccurs while O-glycosylation is absent. The binding strength of these enzymes to fibrin increased withdecrease of the carbohydrate content. The carbohydrate moiety of human type glycosylated t-PA probablymodulates the binding strength of the enzyme to fibrin.

ヒト型糖鎖が結合した組織性プラスミノーゲンアクチベーターの生産とその炭水化物部分の役割

スポンサーリンク

概要

著者

関連論文

スポンサーリンク